Xixuthrus heros ( Heer, 1868 )

Yanega, Douglas, Olson, David, Shute, Sharon & Komiya, Ziro, 2004, The Xixuthrus species of Fiji (Coleoptera: Cerambycidae: Prioninae), Zootaxa 777 (1), pp. 1-10 : 6-7

Xixuthrus heros ( Heer, 1868)

Figs. 3­4

Specimens examined: 1 male, " Viti Lefu " ( BMNH) ; 1 male, Fiji, 1962 N.W. Simmonds ( BMNH) ; 1 male, 1 female, Fiji, Suva , 15.ix.1932, W. Simmonds ( BMNH) ; 1 male, no data ( BMNH) ; 1 male, Fiji, 1953 H. Simmonds ( BMNH) ; 1 male, Fiji, 1905, Fry Coll. ( BMNH) ; 1 male, Fiji, Viti Levu , Lami, 5.vii.1986, coll. Tevita Tuimereke ( MAFF) ; 1 male, Fiji, Viti Levu , Naivikinikini village, 178°24'E, 18°06'S, 30.xii. 2003, 50m, coll. Isikeli Delaivuna ( MAFF) [ Fig. 3 ]; 1 female, Fiji, Viti Levu , Colo­i­Suva Forest Station 22.v.1996 ( MAFF) [ Fig. 4 ]; 1 male, " Fidgi " (Z. Komiya) ; 1 female " Fidsdsi , Tassein Viti Levu " (Z. Komiya) ; 1 male, Viti Levu , Navai Mill, nr. Nandarivatu, 13.ix.1938, 2,400ft. ( BPBM) .

Diagnosis: This species is easily distinguished from the other Fijian species as the elytra have broad glabrous stripes and the flagellomeres (except the distal pair) bear numerous prominent spinules in the male ( Fig. 3 ). Females ( Fig. 4 ) are further distinguished from ganglbaueri by numerous structural features, as mentioned above, including the longer forebasitarsi, apically swollen and spiculate scape, less produced medial pronotal ridges, and longer antennae. A few specimens have the frontal groove nearly as deep as in ganglbaueri , so this feature seems of limited diagnostic value, though we have seen none with elytral pubescence of exactly the same color. Structurally, both sexes of heros are nearly identical to terribilis , though the latter typically have a slightly more elongated vertex ( Figs. 5 & 6 ) and lack elytral stripes. These latter two species share not only the male antennal spinules and long necks and mandibles, but also have the same pronotal and prosternal sculpture, and forebasitarsal proportions, in both sexes.

Remarks: We consider it likely that heros and terribilis are very close sister taxa, and they may or may not be allopatric; anecdotal reports indicate that heros may occur on Vanua Levu (not on Taveuni, contrary to Ryan, 2000), where terribilis has also been found, and the holotype of heyrovskyi is labeled as having come from Viti Levu, though no other specimens have ever been recorded from the island. As mentioned earlier, the holotype of heros is missing, but the identity of the species is not in doubt, so a neotype cannot be designated (following ICZN Article 75.2). A male from Fiji, Viti Levu, Lami, collected in 2004 (not listed above), was selected as a genetic voucher for this species. Komiya (2000) has an excellent habitus photo of a male heros .

Figures

FIGURES 1–6. 1–2. Xixuthrus ganglbaueri Lameere, female neotype: 1, habitus; 2, head, protho­ rax, and forelegs. 3–4. X. heros (Heer): 3, male; head and prothorax; 4, female; head, prothorax, and forelegs. 5–6. X. terribilis Thomson: 5, male holotype of terribilis; head and prothorax; 6, male holotype of heyrovskyi Tippmann [= terribilis]; head.